The transplantation of trees relies basically upon digging-up of trees, carrying of the thus dug up trees to a given position and transplanting thereof. Of importance in this case is that no damage is caused to the roots of the tree. In other words, it is essential to prevent the roots from being torn off or disconnected from the surrounding ground by preventing any extra external force from being applied thereupon. For that reason, a ditch 1 is dug around the roots of the tree as illustrated in FIG. 1, when digging up the tree. After the portions of the roots surrounded by the ditch have been isolated from the remaining portions of the roots, the tree is pulled up, immediately followed by typing.
The aforesaid method is inefficient when the tree is of a large size. To solve the problems associates with this method, it has been proposed to effect digging-up with the use of a power device and to carrying and transplant the tree with the use of a similar power device.
One example is, for instance, illustrated in FIG. 2. An automatic travelling apparatus such as a bulldozer includes a pair of left and right frames 2 and opposite digging scrapers 3 capable of being drivingly pivoted by a driving mechanism in the range from the positions located substantially just below the frames 2 to the positions at which they are closed substantially horizontally in a face-to-face manner (see Japanese Patent Publication No. 57-55371). When the tree is dug up with this apparatus, the digging scrapers 3 are first inserted into the ground surrounding the roots of the tree, and are then pivoted inwardly. According to this system, however, the digging scrapers 3 can cut off the portions of the roots spreading in the left and right directions, but cannot cut off the portions of the roots spreading in the backward, forward and downward directions. Even when the scrapers are pivoted from 3 to a position shown by 3', the tree is not lifted, since the tree is anchored to the ground by the portions of the roots spreading backwardly, forwardly and downwardly. Hence, the roots continue to be clamped between both scrapers 3 and 3, and eventually collapse.
When the scrapers 3 are pivoted from 3' to 3", the roots are forced up. However, the portions of the roots spreading forwardly, backwardly and downwardly are all inevitably torn off. In the end, the tree cannot be transplanted, since the roots collapse.
To transplant a tree T, a transplanting hole 4 is dug at a given location in the earth, and the tree T is slid down in that hole by opening the scrapers 3, as shown in FIG. 3. However, the tree T has a trunk and branches, although not illustrated, and is thus so heavy that its weight is applied upon the roots, when it is slid down in that hole, leading to partial or complete collapse of the roots. In addition, since there are no means for keeping the tree T upright, there is the possibility that the tree will fall.